A wind energy installation such as this is already known in a generic form, for example, from WO 03/014 567 A1 or from U.S. Pat. No. 6,872,049 B2. The wind energy installations disclosed in these documents essentially each comprise a machine housing which is mounted on a machine tower such that it can rotate, having a generator for electricity production, having a wind-driven rotor with a rotor hub to which at least two rotor blades are fitted, and having a large roller bearing, which supports the rotor. In this case, the large roller bearing is generally in the form of a two-row conical roller bearing and has a first bearing ring, which is attached in a rotationally fixed manner to the machine housing and is arranged coaxially with respect to the rotor hub, as well as a second bearing ring, which is held on the first bearing ring such that it can rotate and is attached to the rotor hub, and having a multiplicity of roller bodies which roll between the bearing rings. Furthermore, the large roller bearing is connected to an epicyclic gearbox, which is connected to the generator in the machine housing and comprises, in a known manner, a hollow wheel with a circumferential internal tooth system, a plurality of planet wheels mounted on planet supports, and a central sun wheel, in which the inner of the two bearing rings of the large roller bearing is mounted by means of a push fit on the outer casing surface of the hollow wheel of the epicyclic gearbox.
Furthermore, EP 811 764 A1 also discloses the large roller bearing being connected to the epicyclic gearbox such that the inner of the two bearing rings of the large roller bearing is pressed against a ring which is connected to the rotor hub and is fitted with the planet supports.
However, rotor bearings such as these have the disadvantage that the large roller bearing and the downstream epicyclic gearbox comprise a relatively large number of individual parts and are therefore on the one hand highly costly to manufacture, while on the other hand having a high total weight, which has a highly disadvantageous effect when they are being installed in the machine housing at a height of up to 120 m. Furthermore, both the hollow wheel of the epicyclic gearbox and the inner bearing ring of the large roller bearing, which generally have an external or internal diameter of more than 2.00 m, must be manufactured extremely precisely, despite their size, in order to make it possible to reliably preclude the negative influences, which result from a positive excess fit size and from an excessively tight fit in the push connection between the inner bearing ring and the hollow wheel, on the function of the bearing point or on the tooth system of the epicyclic gearbox. By way of example, an excessively tight fit such as this can on the one hand lead to the inner bearing ring of the large roller bearing widening slightly when it is being mounted on the hollow wheel, and in the radial play which is set in the large roller bearing being too small, thus excessively increasing the friction between the roller bodies and their raceways in the bearing rings. This would result in the maximum permissible operating temperature of the large roller bearing being exceeded, to partial combustion of the lubricant and thus to a lack of lubrication in the large roller bearing, with the large roller bearing in the end failing prematurely. On the other hand, it is also possible for the excessively tight fit between the inner bearing ring of the large roller bearing and the hollow wheel of the epicyclic gearbox to lead to a slight constriction of the hollow wheel, as a result of which the contact points between the internal tooth system on the hollow wheel and the tooth systems on the planet wheels of the epicyclic gearbox changing, with the result that force is no longer transmitted in a defined manner within the epicyclic gearbox, in the worst case leading to teeth breaking on one of the tooth systems.